add _patched_resolve() as workaround for cpython #82852

for python <3.10 on windows

src/tufup/repo/__init__.py

@@ -36,6 +36,7 @@
 from tuf.api.serialization.json import JSONSerializer
 
 from tufup.common import Patcher, SUFFIX_ARCHIVE, SUFFIX_PATCH, TargetMeta
+from tufup.utils.platform_specific import _patched_resolve
 
 logger = logging.getLogger(__name__)
 
@@ -515,9 +516,9 @@ def __init__(
             thresholds: Optional[RolesDict] = None,
     ):
         if repo_dir is None:
-            repo_dir = pathlib.Path.cwd() / DEFAULT_REPO_DIR_NAME
+            repo_dir = DEFAULT_REPO_DIR_NAME
         if keys_dir is None:
-            keys_dir = pathlib.Path.cwd() / DEFAULT_KEYS_DIR_NAME
+            keys_dir = DEFAULT_KEYS_DIR_NAME
         if key_map is None:
             key_map = deepcopy(DEFAULT_KEY_MAP)
         if encrypted_keys is None:
@@ -529,8 +530,8 @@ def __init__(
         self.app_name = app_name
         self.app_version_attr = app_version_attr
         # force path object and resolve, in case of relative paths
-        self.repo_dir = pathlib.Path(repo_dir).resolve()
-        self.keys_dir = pathlib.Path(keys_dir).resolve()
+        self.repo_dir = _patched_resolve(pathlib.Path(repo_dir))
+        self.keys_dir = _patched_resolve(pathlib.Path(keys_dir))
         self.key_map = key_map
         self.encrypted_keys = encrypted_keys
         self.expiration_days = expiration_days

src/tufup/utils/platform_specific.py

@@ -240,3 +240,20 @@ def _install_update_mac(
     logger.debug(f'Restarting application, running {sys.executable}.')
     subprocess.Popen(sys.executable, shell=True)  # nosec
     sys.exit(0)
+
+
+def _patched_resolve(path: pathlib.Path):
+    """
+    this is a rather crude workaround for cpython issue #82852,
+    where Path.resolve() yields a relative path, on windows, if the target
+    does not exist yet
+
+    https://github.com/python/cpython/issues/82852
+
+    todo: remove this as soon as support for python 3.9 is dropped
+    """
+    if ON_WINDOWS and sys.version_info[:2] < (3, 10):
+        logger.warning('using patched path for cpython #82852')
+        if not path.is_absolute():
+            path = pathlib.Path.cwd() / path
+    return path.resolve()